diff options
Diffstat (limited to 'src/libshared/base-filesystem.c')
| -rw-r--r-- | src/libshared/base-filesystem.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/libshared/base-filesystem.c b/src/libshared/base-filesystem.c new file mode 100644 index 0000000000..59a34a9d11 --- /dev/null +++ b/src/libshared/base-filesystem.c @@ -0,0 +1,129 @@ +/*** + This file is part of systemd. + + Copyright 2014 Kay Sievers + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <fcntl.h> +#include <stdbool.h> +#include <stdlib.h> +#include <sys/stat.h> +#include <syslog.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "base-filesystem.h" +#include "fd-util.h" +#include "log.h" +#include "macro.h" +#include "string-util.h" +#include "umask-util.h" +#include "user-util.h" +#include "util.h" + +typedef struct BaseFilesystem { + const char *dir; + mode_t mode; + const char *target; + const char *exists; + bool ignore_failure; +} BaseFilesystem; + +static const BaseFilesystem table[] = { + { "bin", 0, "usr/bin\0", NULL }, + { "lib", 0, "usr/lib\0", NULL }, + { "root", 0755, NULL, NULL, true }, + { "sbin", 0, "usr/sbin\0", NULL }, + { "usr", 0755, NULL, NULL }, + { "var", 0755, NULL, NULL }, + { "etc", 0755, NULL, NULL }, +#if defined(__i386__) || defined(__x86_64__) + { "lib64", 0, "usr/lib/x86_64-linux-gnu\0" + "usr/lib64\0", "ld-linux-x86-64.so.2" }, +#endif +}; + +int base_filesystem_create(const char *root, uid_t uid, gid_t gid) { + _cleanup_close_ int fd = -1; + unsigned i; + int r = 0; + + fd = open(root, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW); + if (fd < 0) + return log_error_errno(errno, "Failed to open root file system: %m"); + + for (i = 0; i < ELEMENTSOF(table); i ++) { + if (faccessat(fd, table[i].dir, F_OK, AT_SYMLINK_NOFOLLOW) >= 0) + continue; + + if (table[i].target) { + const char *target = NULL, *s; + + /* check if one of the targets exists */ + NULSTR_FOREACH(s, table[i].target) { + if (faccessat(fd, s, F_OK, AT_SYMLINK_NOFOLLOW) < 0) + continue; + + /* check if a specific file exists at the target path */ + if (table[i].exists) { + _cleanup_free_ char *p = NULL; + + p = strjoin(s, "/", table[i].exists, NULL); + if (!p) + return log_oom(); + + if (faccessat(fd, p, F_OK, AT_SYMLINK_NOFOLLOW) < 0) + continue; + } + + target = s; + break; + } + + if (!target) + continue; + + r = symlinkat(target, fd, table[i].dir); + if (r < 0 && errno != EEXIST) + return log_error_errno(errno, "Failed to create symlink at %s/%s: %m", root, table[i].dir); + + if (uid != UID_INVALID || gid != UID_INVALID) { + if (fchownat(fd, table[i].dir, uid, gid, AT_SYMLINK_NOFOLLOW) < 0) + return log_error_errno(errno, "Failed to chown symlink at %s/%s: %m", root, table[i].dir); + } + + continue; + } + + RUN_WITH_UMASK(0000) + r = mkdirat(fd, table[i].dir, table[i].mode); + if (r < 0 && errno != EEXIST) { + log_full_errno(table[i].ignore_failure ? LOG_DEBUG : LOG_ERR, errno, + "Failed to create directory at %s/%s: %m", root, table[i].dir); + + if (!table[i].ignore_failure) + return -errno; + } + + if (uid != UID_INVALID || gid != UID_INVALID) { + if (fchownat(fd, table[i].dir, uid, gid, AT_SYMLINK_NOFOLLOW) < 0) + return log_error_errno(errno, "Failed to chown directory at %s/%s: %m", root, table[i].dir); + } + } + + return 0; +} |